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81.
82.
The concept of data in the humanistic academy carries a heavycultural freight: as a reductionist yet efficient representationof complex textual significance. Far from being an inventionof the digital age, this conception of the role of quantificationhas a prehistory whose terms continue to resonate in moderndebates about digital editing and digitally mediated scholarship.This essay explores these terms and the anxieties they reflect,concluding that digital representation is no less textuallyand methodologically rich, and no less a production of knowledge,than its print counterpart. 相似文献
83.
In this paper, a scheduling problem that occurs in potash mining is introduced, where a block excavation sequence has to be found taking into account a limited number of underground machines as well as safety-related restrictions. The aim is to minimize the maximum completion time of excavations, i.e., the makespan. The resulting problem can be transformed into a hybrid flow shop scheduling problem with reentry, unrelated machines, and job-precedences. A mixed-integer linear model is presented and small-scale instances are solved with CPLEX. In order to tackle medium- and large-scale instances heuristically, a basic and an advanced multi-start algorithm are developed, based on a specific priority rule-based construction procedure. In addition, a modified version of the Giffler and Thompson procedure is applied. Computational experiments are conducted on problem instances derived from real-world data in order to evaluate the performances of the proposed solution procedures. 相似文献
84.
The genomic distance problem in the Hannenhalli–Pevzner (HP) theory is the following: Given two genomes whose chromosomes are linear, calculate the minimum number of translocations, fusions, fissions and inversions that transform one genome into the other. This paper presents a new distance formula based on a simple tree structure that captures all the delicate features of this problem in a unifying way, and a linear time algorithm for computing this distance. 相似文献
85.
Julia Armesto Izabela Lubowiecka Celestino Ordóñez Fernando I. Rial 《Automation in Construction》2009,18(5):559-569
The aim of this paper is to present a methodology for the evaluation of historic timber structures, based on numerical modeling coupled with on site measurements. A method to measure the geometry of structural elements of a timber roof using a photogrammetric modeling procedure is described. In particular, we show the utility of photogrammetric based models when applied to structural analysis by directly introducing 3D geometry files in the preprocessing module of computational software based on the Finite Element Method. The 2D and 3D FEM models of the roof are considered to compare the simple and more complex modeling, and static and dynamic analyses are performed. Both models are prepared using the photogrammetric data. 相似文献
86.
Neiworth Julie J.; Johnson Elizabeth T.; Whillock Katherine; Greenberg Julia; Brown Vanessa 《Canadian Metallurgical Quarterly》2009,123(1):10
To address a controversy in the literature concerning whether monkeys show an aversion to inequity, individuals of a New World monkey species, cotton top tamarins (Saguinus oedipus) were tested in an offering task and in a bartering task. At issue was whether the monkeys rejected rewards because of a violation of expectancy of the preferred reward, or whether they rejected rewards because of a sensitivity to socially mediated inequity. The data from both tasks indicated that the subjects were more likely to reject when preferred rewards were presented, either because of another animal eating the reward (the social condition) or because of rewards being presented but inaccessible. The bartering task led to the only behavioral indication of aversion due specifically to social inequity, which was demonstrated when tamarins' sensitivity to the difference in rewards increased with exposure to other tamarins working to receive the preferred rewards. The results suggest that social inequity aversion will be assessed by tamarins, and possibly by other primates, only under conditions of limited resources and a requirement of work, which may make the situation a bit more competitive and thus drives attention toward both social and reward evaluation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Celestino Ordóñez Joaquín Martínez Pedro Arias Julia Armesto 《Automation in Construction》2010,19(6):742-749
The dimensions of façades and window openings are usually determined by direct measurements using tapes and plummets. These direct methods are time consuming and risky for operators, so indirect approaches are needed. In this paper, we analyse a planar-surface measuring system based on close-range photogrammetry to determine its accuracy and precision. This system is composed of a digital camera and a laser distance meter mounted on a support that allows the laser distance meter to be moved independently of the camera. The proposed system can determine the dimensions of objects. Also, this system provides an estimation of the precision of the calculations for the distances between points. By knowing the uncertainty of their measurements, users can accept or reject the measurement depending on the application tolerance. 相似文献
88.
89.
Anne Freudenstein Julia Weking Bertrand Matthäus 《European Journal of Lipid Science and Technology》2013,115(3):286-294
To find new ways for reducing the potential of palm oil to form 3‐monochloropropane‐1,2‐diol (3‐MCPD) and glycidyl esters during refining it is helpful to know more about the influence of different precursors like diacylglycerols (DAGs) and monoacylglycerols (MAGs), lecithin, and chlorine containing compounds. After adding increasing amounts of the different precursors to a model oil obtained by removal of polar compounds from crude palm oil and heating the mixture under standardized conditions to 240°C for 2 h the contents of 3‐MCPD and glycidyl esters were analyzed according to the standard procedure of DGF C‐VI 18 (10). DAGs and MAGs were found to increase the potential of palm oil to form 3‐MCPD and glycidyl esters, but refined lecithin showed no influence. Sodium chloride as well as tetra‐n‐butylammoniumchloride (TBAC) led to higher contents of the esters. Whereas the addition of TBAC raised the amount of glycidyl esters as well as 3‐MCPD esters, sodium chloride largely raised the amount of 3‐MCPD esters. An addition of 5 mmol of sodium carbonate/kg model oil spiked with sodium chloride reduced the amount of glycidyl esters almost completely; the 3‐MCPD esters were reduced by 50%. About 1 mmol sodium hydrogen carbonate/kg oil reduced both 3‐MCPD and glycidyl esters almost completely. Practical applications : For the mitigation of the formation of 3‐MCPD esters and related compounds in refined edible oils, it is helpful to know more about the effect of different possible precursors. Using a broader data basis, it is possible to adopt the oil processing but especially the choice of the raw material to the demands of the market for lower contents of the esters in the refined products. 相似文献
90.
Julia Romero‐Pastor José Vicente Navarro Marian del Egido Miguel Ortega‐Huertas 《Journal of the American Ceramic Society》2013,96(7):2132-2140
We studied ancient enamels on gilded copper from a collection of archeological horse harness pendants of the Museo Instituto Valencia de Don Juan (Madrid, Spain) to test the benefits of a new, nondestructive analytical methodology based on chemometric analysis (i.e., Principal Component Analysis, PCA) on micro‐ATR‐FTIR spectral data and chemical quantification using SEM‐EDS. The novelty of this approach was threefold: (i) PCA allowed the discrimination of the different harness pendants of known origin and attributed to the 14th and 15th centuries according to the chemical complex composition, nanostructure, glass weathering, and/or coloring mechanisms of each colored enamel, separately (i.e., red, purple, blue, and white), (ii) it is a cheap, easily available and nondestructive methodology that enables us to (iii) draw archeological conclusions about the quality of the manufacturing process, reassess the chronology of these objects and attempt to attribute them to different workshops according to the different traditional recipes identified. In particular, the enamels were made of alkali and/or alkaline earth lead‐glass with a wide range of chemical compounds in the form of pigments or opacifiers. Two types of coloring mechanisms were identified, colloidal particles such as copper‐ruby for red enamels, and ionic mechanisms such as Fe(II) and Co(II) to achieve a blue pigments; Mn(III) in the purple pigment; and two kind of white enamels were identified, i.e., tin oxide as an opacifier and uranium oxide. In addition, we established the reason for the poor state of conservation of some of the enamels by means of the identification of depolymerization and ion exchanges, well‐known harmful effects of glass weathering, and finally a chronology was assigned for some of these pieces according to the enamel composition. 相似文献